Diagnostic Instructions

•	Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

•	Review Strategy Based Diagnosis for an overview of the diagnostic approach.

•	Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0500

Vehicle Speed Sensor Circuit

DTC P0501

Vehicle Speed Sensor Performance

DTC P0502

Vehicle Speed Sensor Circuit Low Voltage

DTC P0503

Vehicle Speed Sensor Circuit Intermittent

Circuit/System Description

The transmission control module (TCM) provides the engine control module (ECM) vehicle speed information through the high-speed communication on the controller area network (CAN). Vehicle speed is obtained through the alternating current (AC) which is created by the sensor for the rotation speed (OSS) of the gearbox output shaft when the output shaft is rotating. The ECM continuously monitors the vehicle speed signal provided by the TCM.

Conditions for Running the DTC

•	Engine coolant temperature is more than 39.8°C (104°F).

•	No engine coolant temperature DTC is set.

•	No engine speed sensor DTC is set.

•	The DTCs runs continuously when the above condition are met.

Conditions for Setting the DTC

P0500

The ECM detects the vehicle speed is less than 5 km/h (3 MPH) for more than 5 s.

P0501

The ECM detects the CAN signal is not valid for more than 2 s.

P0502

The ECM detects the actual vehicle speed is equal to the last vehicle speed for more than 10 s.

P0503

The ECM detects the vehicle speed is greater than 275 km/h (171 MPH) for more than 0.2 s.

Action Taken When the DTC Sets

•	DTCs P0500, P0502, and P0503 are Type B DTCs.

•	DTC P0501 is a Type C DTC.

Conditions for Clearing the DTC

•	DTCs P0500, P0502, and P0503 are Type B DTCs.

•	DTC P0501 is a Type C DTC.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

•	Circuit Testing

•	Connector Repairs

•	Testing for Intermittent Conditions and Poor Connections

•	Wiring Repairs

Description and Operation

Transmission Component and System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1.	Ignition On, observe the DTC information with a scan tool. Verify no TCM or communication DTCs are set.

2.	If any TCM or communication DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

3.	Raise the drive wheels.

4.	Warning Support the lower control arms in the normal horizontal position in order to avoid damage to the drive axles. Do not operate the vehicle in gear with the wheels hanging down at full travel. Support the lower control arms so that the drive axles are in a horizontal position.

5.	Engine running, place the transmission into 2nd gear.

6.	Observe the scan tool Vehicle Speed parameter. The following should display a similar vehicle speed once the drive wheels are at a speed above 5 km/h (3 MPH):

•

The scan tool Vehicle Speed parameter

•

The odometer value

7.	Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

8.	If the DTC resets, replace the ECM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•	ECM or TCM-Refer to Control Module References for replacement, setup and programming.

•	Perform the Transmission Adaptive Functions.